Method of and apparatus for combining strands



V. L. JOHANNESSEN ET AL METHOD OF AND APPARATUS FOR COMBINING STRANDS Filed July 9, 1936 2 Sheets-Sheet 1 FIG! INVE N TORS L.JOH.4IVNE$SEN 0.0. MERR/CK Oct. 12, 1937. v. L. JOHANNESSEN ET AL 2,095,551

METHOD OF AND APPARATUS FOR COMBINING STRANDS Filed July 9; 1936 2 Sheets-Shet 2 RUBBER v INVENTORS V.L. JOHANNESSEN 0.0. MERR/CK A TTORNEY UNITED STATES PATEN Patented a. 12, 1937 METHOD OF AND APPARATUS FOR COM- BINING STRANDS Application July 9, 1936, Serial No. 89,812

Claims. (Cl. 117-34) T OFFICE This invention relates to a method of and apparatus for combining strands and more Particularly to a method of and apparatus for intertwisting strands with predetermined cyclic varia- 5 tions of lay.

In the manufacture of electric cables, especially such as are used in the communications- 1 ing such capacitance balancing units, as they may be called, is to intertwist two appropriate strands in such fashion that they are twisted together, with a non-conductive core strand, with a very short pitch of lay in a close double helix for a predetermined distance and then for an other predetermined distance with a very long or practically no twist. The closely twisted portions may then be cut apart at some point between for use. a

An object of the present invention is to provide a method of and an apparatus for intertwisting two or more strands with or without a core strand in such fashion as to produce a repeated sequence of two or more portions having lays of different pitch.

One embodiment of the invention contemplates an apparatus for intertwisting strands having rotatable strand supplies, means to bring the strand together to be intertwisted by rotation of the supplies and means to propel the strands from the supplies through the apparatus in combination with means to cyclically alter the longitudinal speed of the strands through the intertwisting means.

Other objects and features of the invention will appear from the following detailed description of one embodiment of the invention taken in connection with the accompanying drawings in which the same reference numerals are applied to identical parts in the several figures and in which Fig. 1 is a diagrammatic viewin side elevation of'an apparatus for twisting strands together,

50 constructed in accordance with the invention;

Fig. 2 is an enlarged view in vertical central section of thecompacting and guiding device;

Fig. 3 is a plan view of the lower member thereof;

55 Fig. 4 is a detached view of the control cam;

5 is a view similar to Fig. 4 of a modified form of the control cam;

Fig. 6 is a view of a portion of the product of the apparatus when controlled by the cam shown in Fig. 4, and

Fig. 7 is a view of a portion of the product of the apparatus when controlled by the cam shown in Fig. 5.

As disclosed in Figs. 1, 2, 3 and 4, the apparatus comprises means 20 to support a supply 2| of core strand 22. which may be thought of for illustration as a non-conductive textile cord in a supporting member 24. A conductor supply support 25 is rotatably mounted on the member 24 to be driven by gears 26, 21 and 28 from a shaft 23 driven by a motor 295/ Supplies 30 and 3| of conductor strands 32 and 33 are mounted on the support 25 to rotate thereon and revolve therewith. In the center of the support is mounted an upwardly extending member 34 having at its upper end a .conical twisting head 35 and throughout its length an axial bore 36 which continues down through the support 25 and through which the core strand 22 passes up. Guide grooves 31 .and 38 are formed in the top surface of the head 35 to receive the strands 32 and 33 from the supplies 30 and 3|, and to lead the strands 32 and 33 to the core strand 22 where the latter emerges from the bore 36 at the tip of the head 35.

Immediately above the head 35 and coacting therewith is a stationary member 39 having a vertical bore 40 aligned with the bore 36 and in effect a continuation thereof. The lower end of the member 39 is formed with a conoidal entrance 4| to the bore 40, which matches the conical contour of the head 35 and is closely approximated thereto. Recesses 42 and 43 are formed within the member 39 and communicating with the bore 40. In the recess 43 is mounted a pair of fixedly positioned rubber faced rolls 44 and45. A lever arm 46 pivoted on the member 39 above the recess 42 carries a third rubber faced roll 41 movably positioned in the recess 42 opposite the juncture of the rolls 44 and 45 and pressed toward these rolls by the action of a spring 48 attached to the lever 46 and to the member 39. The three strands 22, 32 and 33 combined into a single compound strand 50 passes up between the rolls 44 and 45 onone side and the roll 41 on the other through the bore 40.

The strand 50 passes from the bore 40 up and over a sheave 5i mounted to rotate freely in one end of a lever 52pivotally mounted at 53 on a stationary support. A cam roller 54 is borne by the other end of the lever and coacts with a cam 55 rigidly secured on the shaft 56 of a capstan 51 driven by the motor 29. The strand 50 passes from the sheave and one or more times around the capstan 51 to be advanced thereby, and from the capstan to a take-up device 58 of any approved construction.

When, in operation, the roller 54 is running over the cam 5| from A via B to C, the sheave 5| sinks slowly at a constant rate and hence the strand 50 is drawn up from the bore 40 by the capstan 51 at a low rate of constant speed, more slowly than the strand beyond the capstan is being wound on the take-up 58. During this time, because of the relatively slow longitudinal advance of the strand 5!] from the compacting die 39, the strands 32 and 33 are being laid up together about the core strand 22 by the action of the base 25 and the head 35 with short pitch and closely approximated turns, as indicated at 60 in Fig. 6.

When the cam has turned under the roller past the point C, the roller drops abruptly down the cam from C via D to E, and the sheave 5| moves swiftly from the full line position of Fig. 1 to the dotted line position dragging an equivalent length of the strands (6| in Fig. 6) from the several supplies. Since this portion of the strands is drawn thus through the twisting device at a much greater longitudinal speed and without any change in the speed of the base 25, the strands 32 and 33 are here twisted together about the core 22 with a much longer pitch, even, if the action of the cam from C to D to E be swift enough, with practically no twist as shown.

At the end of this period of swift withdrawal, there will be between the exit end of the twisting head bore 36 and the rolls 45 and 41 a length of relatively twistless combined strands. Hence from E to A, the cam is formed to give the roller 54 a short, swift lift and hence to make the sheave 5| drop swiftly for a short distance at such a rate and for such a time that no pull is exerted on the strands until the portion of the strands between the. tip of the head 35 and the grip of the rollers 45 and 41 is twisted tightly to form the initial fraction of a portion 60 of the combined strand.

The process described is then repeated cyclically as long as the machine runs, and hence produces the product shown in Fig. 6 with the strands 32 and 33 intertwisted about the strand 22 in alternate cyclically repeated portions 60 and SI of difiering twist.

By making the cam 55 interchangeable for others of different contours of the same general form the ratio of the pitches of the twists at 60 and GI may be given practically any desired value; or, as shown in Fig. 5, if the form of .contour of the cam be varied as well as its proportions, a sequence of more than two portions each diflering from its predecessor and successor in pitch, may be made in cyclical repetition. Such a product is illustrated in Fig.7 where the portions 82, 63, SI, 55, 66, i1, 68 and 59 have twists due respectively to the portions F--G, GH, HK, K-L, L-M, M-P, P-R and R-F of the cam I55.

In any case the pitch of the twist at any given moment is governed by the motion of the sheave 5|, as it depends upon'the longitudinal speed of the strand 5! being pulled from the head 35, which latter rotates at'unvarying speed. 'Ihus a characterizing feature or the invention is the fact that the strands are pulled at a predetermin edly and cyclically varying longitudinal speed through a twisting head rotating at an unvarying rate. Another feature is that the longitudi nal speed of the strands at any given moment is the algebraic sum of the effects of the capstan 51 and of the sheave 5 I, the capstan running at substantially constant speed and so determining the average rate of longitudinal advance of the strands, while the sheave alternately adds to and subtracts from this rate of advance. Although the apparatus herein disclosed operates on a core and two conductors, it is evident that the number of conductors may be changed without materially altering the machine or its operation.

Patentable subject matter disclosed but not claimed herein, is claimed in copending application Serial Number 89,814 filed on the same date herewith by H. S. Keating, the inventor thereof.

The embodiment herein disclosed is illustrative only and may be widely departed from and modified in many ways without departing from the spirit and scope of the invention as pointed out in and limited only by the appended claims.

What is claimed is:

1. In a strand handling apparatus having means to intertwist a plurality of strands comprising a rotary twisting member running at substantially constant angular speed, means to advance a plurality of strands through the apparatus at a constant longitudinal speed, and means to alternately increase and diminish the longitudinal speed of the portion of the strands passing the twisting member by alternately creating slack in and removing slack from the strands between the twisting member and the advancing means.

2. In a strand handling apparatus having means to intertwist a plurality of strands comprising a rotary twisting member running at substantially constant angular speed, means to advance a plurality of strands through the apparatus at a constant longitudinal speed, and means to cyclically increase and diminish the longitudinal speed of the portion of the strands passing the twisting member by cyclically creating slack in and removing slack from the strands between the twisting member and the advancing means.

3. In a strand handling apparatus, a rotary twisting member running at constant angular speed, means to advance a strand from the twisting member, a sheave over which the strand passes between the twisting member and the advancing means, and means to move the sheave to cyclically vary the length of path of the strand from the member to the advancing means.

4; In a strand handling apparatus, a rotary twisting member running at constant angular speed, means to advance a strand from the twisting member, a sheave over which the strand passes between the twisting member and the advancing means, and a cam to move the sheave to cyclically vary the length of path of the strand from the member to the advancing means.

5. In a strand handling apparatus, a rotary twisting member running at constant angular speed, means to advance a strand from the twisting member, a sheave over which the strand passes between the twisting member and the advancing means, and a cam driven by the advancing means to move the sheave to cyclically vary the length of path of the strand from the member to the advancing means.

6. A method of combining strands which comprises the steps of advancing a plurality of strands longitudinally at constant speed from supplies thereof to a constant speed take-up-therefor, and intertwisting the strands together at a constant time rate of rotation of the strands about a common axis at a point between the supply and the take-up, while alternately decreasing and increasing the longitudinal speed of the strands at the twisting point by alternately creating and removing slack in and from the intertwisted strands between the twisting point and the take-up.

7. In a strand handling apparatus having means to intertwist a plurality of strands comprising a rotary twisting member running at substantially constant angular speed, means to advance a plurality of strands through the apparatus at a constant longitudinal speed, and means interposed between the twisting member and the advancing means to alter the longitudinal speed of the portion of the strands passing the twisting member by altering the length of path of the strands from the twisting member to the strand advancing means.

8. In a strand handling apparatus having means to intertwist a plurality of strands comprising a rotary twisting member running at substantially constant angular speed, means to advance a plurality of strands through the apparatus at a constant longitudinal speed, and means interposed between the twisting member and the advancing means to cyclically alter the longitudinal speed of the'portion of the strands passing length of path of the strands from the twisting member to the strand advancing means.

9. In a strand handling apparatus having means to intertwist a plurality of strands comprising a rotary twisting member running at substantially constant angular speed, means to advance a plurality of strands through the apparatus at a constant longitudinal speed, and means interposed between the twisting member and the advancing means to alternately increase and decrease the longltudinal'speed of the portion of the strands passing the twisting member by alterthe twisting member by cyclically altering the nately increasing and decreasing the length of path of the strands from the twisting member to thestrand advancing means.

10. A method of combining strands which comprises the steps of advancing a plurality of strands longitudinally at constant speed from supplies thereof to a constant speed take-up therefor, and

'intertwisting the strands together at a constant time rate of rotation of the strands about a common axis at a point between the supply and the take-up, while alternately decreasing and increasing the longitudinal speed of the strands at the twisting point by alternately increasing and diminishing the length of path of the strands from the twisting point to the take-up.

VAUGHN L. JOHANNESSEN. DE WI'I'I D. MERRICK. 

